According to the journal Nature Astronomy reported on Monday, Oct. 25, a potential planet was first discovered outside the Milky Way through the Chandra X-ray Observatory.
The findings exhibit a new technique that has the potential of figuring out planets in a wide range of systems hosting [X-ray sources].
In an arm of the magnificent Whirlpool Galaxy, astronomers detected a potential planet named M51-ULS-1b outside our galaxy, around 28 million light-years away.
The spotted object, which has the approximate size of Saturn, orbits around a giant star and a smaller dense core of a dead star known as a neutron star or a black hole.
When the object passed in front of its binary stars, it caused a dip in X-ray emissions, which were produced by the neutron star or black hole sucking gas from its companion. The transit took about three hours.
Astronomers used dips in visible light to spot alien planets in our own galaxy, this is known as the transit technique. However, the team admitted that X-rays allowed them to detect objects hard to spot.
The study’s lead author Rosanne Di Stefano of the Center for Astrophysics Harvard & Smithsonian, said in a statement: “We are trying to open up a whole new arena for finding other worlds by searching for planet candidates at X-ray wavelengths, a strategy that makes it possible to discover them in other galaxies.”
Although hints indicated the possibility of a planet, more works should be done thoroughly before placing any formal announcement.
Jonti Horner, a professor of the University of Southern Queensland, doubted what the astronomers had captured. He stated that we would have to be extremely fortunate to have caught a planet at the right time because it takes 70 years for the potential planet to orbit its suns, traveling twice as far as Saturn does to our sun.
He explained that the planet has to emerge lining up in the proper position, at the right time, in which we can see it.
The astrophysicist, specialized in alien planet research, said: “If you took observations a million times at random over that 70 years, only on four of those times would you see this thing transiting it,” as ABC News reported.
He indicated that using the same technique, they had confirmed only one planet within our galaxy, the Milky Way, with orbits of around ten years.
“It seems too much an outlier, especially with a new technique,” he added.
According to Horner, it’s indeed challenging to identify objects orbiting binary targets emitting high energy.
He concluded: “There’s always a chance they got lucky, but I think it’s more likely that there’s something else going on causing this signal.”